fix(jest): pass findRelatedTests files as trailing positional args (fixes #1859)

packages/jest/src/options-converter.spec.ts

@@ -31,4 +31,23 @@ describe('Convert options to Jest CLI arguments', () => {
     const argv = optionsConverter.convertToCliArgs({ '--': ['non-flag-1', 'non-flag-2'] } as any);
     expect(argv).toEqual(['non-flag-1 non-flag-2']);
   });
+
+  // --- findRelatedTests regression tests ---
+  // Jest treats --findRelatedTests as a boolean flag; source files are positional
+  // args (yargs `_`). Angular CLI delivers array schema fields as a proper string[].
+  describe('findRelatedTests', () => {
+    it('should emit --findRelatedTests once and files as trailing positionals (single file)', () => {
+      const argv = optionsConverter.convertToCliArgs({
+        findRelatedTests: ['src/foo.spec.ts'],
+      } as any);
+      expect(argv).toEqual(['--findRelatedTests', 'src/foo.spec.ts']);
+    });
+
+    it('should emit --findRelatedTests once and files as trailing positionals (multiple files)', () => {
+      const argv = optionsConverter.convertToCliArgs({
+        findRelatedTests: ['src/foo.spec.ts', 'src/bar.spec.ts'],
+      } as any);
+      expect(argv).toEqual(['--findRelatedTests', 'src/foo.spec.ts', 'src/bar.spec.ts']);
+    });
+  });
 });

packages/jest/src/options-converter.ts

@@ -1,13 +1,31 @@
 import { SchemaObject as JestBuilderSchema } from './schema';
 
+/**
+ * Options that Jest treats as a boolean flag with file paths as trailing positional
+ * arguments (parsed via yargs `_`). For these options the converter emits the flag
+ * once and appends every path as a bare positional at the end of argv.
+ *
+ * Example: `--findRelatedTests file1.ts file2.ts`
+ * Jest yargs parsing: `findRelatedTests=true`, `_=['file1.ts', 'file2.ts']`
+ */
+const POSITIONAL_ARRAY_OPTIONS = new Set(['findRelatedTests']);
+
 export class OptionsConverter {
   convertToCliArgs(options: Partial<JestBuilderSchema>): string[] {
     const argv = [];
+    const positionalArgs: string[] = [];
     let nonFlagArgs: string | undefined;
+
     for (const option of Object.keys(options)) {
-      let optionValue = options[option];
-      if (option == '--') {
+      const optionValue = options[option];
+
+      if (option === '--') {
         nonFlagArgs = (optionValue as string[]).join(' ');
+      } else if (POSITIONAL_ARRAY_OPTIONS.has(option)) {
+        // These options use a boolean flag + trailing positional file paths.
+        // Angular CLI delivers them as a proper string array (one element per file).
+        argv.push(`--${option}`);
+        positionalArgs.push(...(optionValue as string[]));
       } else if (optionValue === true) {
         argv.push(`--${option}`);
       } else if (typeof optionValue === 'string' || typeof optionValue === 'number') {
@@ -18,9 +36,11 @@ export class OptionsConverter {
         }
       }
     }
+
     if (nonFlagArgs) {
       argv.push(nonFlagArgs);
     }
-    return argv;
+
+    return [...argv, ...positionalArgs];
   }
 }

packages/jest/tests/integration.js

@@ -106,7 +106,6 @@ module.exports = [
     command:
       'node ../../../packages/jest/tests/validate.js my-shared-library --find-related-tests projects/my-shared-library/src/lib/my-shared-library.service.ts projects/my-shared-library/src/lib/my-shared-library.component.ts --expect-suites=2 --expect-tests=2',
   },
-
   // E2E sanity
   {
     id: 'e2e-simple-app',